/*  -*-c++-*- 
 *  Copyright (C) 2008 Cedric Pinson <cedric.pinson@plopbyte.net>
 *
 * This library is open source and may be redistributed and/or modified under  
 * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or 
 * (at your option) any later version.  The full license is in LICENSE file
 * included with this distribution, and on the openscenegraph.org website.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
 * OpenSceneGraph Public License for more details.
 *
 * Authors:
 *         Cedric Pinson <cedric.pinson@plopbyte.net>
 *         Michael Platings <mplatings@pixelpower.com>
 */

#ifndef OSGANIMATION_CHANNEL_H
#define OSGANIMATION_CHANNEL_H

#include <osgAnimation/Export>
#include <osgAnimation/Sampler>
#include <osgAnimation/Target>
#include <osg/Referenced>
#include <string>

namespace osgAnimation
{

    class OSGANIMATION_EXPORT Channel : public osg::Referenced
    {
    public:

        Channel();
        Channel(const Channel& channel);
        virtual ~Channel();
        virtual Channel* clone() const = 0;

        virtual void update(float time, float weight, int priority) = 0;
        virtual void reset() = 0;
        virtual Target* getTarget() = 0;
        virtual bool setTarget(Target*) = 0;

        const std::string& getName() const;
        void setName(const std::string& name);

        virtual float getStartTime() const = 0;
        virtual float getEndTime() const = 0;

        const std::string& getTargetName() const;
        void setTargetName(const std::string& name);

        virtual Sampler* getSampler() = 0;
        virtual const Sampler* getSampler() const = 0;

        // create a keyframe container from current target value
        // with one key only, can be used for debug or to create
        // easily a default channel from an existing one
        virtual bool createKeyframeContainerFromTargetValue() = 0;

    protected:
    
        std::string _targetName;
        std::string _name;
    };


    template <typename SamplerType>
    class TemplateChannel : public Channel
    {
    public:

        typedef typename SamplerType::UsingType UsingType;
        typedef TemplateTarget<UsingType> TargetType;
        typedef TemplateKeyframeContainer<typename SamplerType::KeyframeType> KeyframeContainerType;
        Channel* clone() const { return new TemplateChannel<SamplerType>(*this); }

        TemplateChannel (const TemplateChannel& channel) :
            Channel(channel)
        {
            if (channel.getTargetTyped())
                _target = new TargetType(*channel.getTargetTyped());

            if (channel.getSamplerTyped())
                _sampler = new SamplerType(*channel.getSamplerTyped());
        }

        TemplateChannel (SamplerType* s = 0,TargetType* target = 0)
        {
            if (target)
                _target = target;
            else
                _target = new TargetType;
            _sampler = s;
        }

        virtual bool createKeyframeContainerFromTargetValue()
        {
            if (!_target.valid()) // no target it does not make sense to do it
            {
                return false;
            }

            // create a key from current target value
            typename KeyframeContainerType::KeyType key(0, _target->getValue());
            // recreate the keyframe container
            getOrCreateSampler()->setKeyframeContainer(0);
            getOrCreateSampler()->getOrCreateKeyframeContainer();
            // add the key
            _sampler->getKeyframeContainerTyped()->push_back(key);
            return true;
        }

        virtual ~TemplateChannel() {}
        virtual void update(float time, float weight, int priority) 
        {
            // skip if weight == 0
            if (weight < 1e-4)
                return;
            typename SamplerType::UsingType value;
            _sampler->getValueAt(time, value);
            _target->update(weight, value, priority);
        }
        virtual void reset() { _target->reset(); }
        virtual Target* getTarget() { return _target.get();}
        virtual bool setTarget(Target* target)
        {
            _target = dynamic_cast<TargetType*>(target);
            return _target.get() == target;
        }

        SamplerType* getOrCreateSampler()
        {
            if (!_sampler.valid())
                _sampler = new SamplerType;
            return _sampler.get();
        }

        Sampler* getSampler() { return _sampler.get(); }
        const Sampler* getSampler() const { return _sampler.get(); }

        SamplerType* getSamplerTyped() { return _sampler.get();}
        const SamplerType* getSamplerTyped() const { return _sampler.get();}
        void setSampler(SamplerType* sampler) { _sampler = sampler; }

        TargetType* getTargetTyped() { return _target.get(); }
        const TargetType* getTargetTyped() const { return _target.get(); }
        void setTarget(TargetType* target) { _target = target; }

        virtual float getStartTime() const { return _sampler->getStartTime(); }
        virtual float getEndTime() const { return _sampler->getEndTime(); }

    protected:
        osg::ref_ptr<TargetType> _target;
        osg::ref_ptr<SamplerType> _sampler;
    };


    typedef std::vector<osg::ref_ptr<osgAnimation::Channel> > ChannelList;

    typedef TemplateChannel<DoubleStepSampler> DoubleStepChannel;
    typedef TemplateChannel<FloatStepSampler> FloatStepChannel;
    typedef TemplateChannel<Vec2StepSampler> Vec2StepChannel;
    typedef TemplateChannel<Vec3StepSampler> Vec3StepChannel;
    typedef TemplateChannel<Vec4StepSampler> Vec4StepChannel;
    typedef TemplateChannel<QuatStepSampler> QuatStepChannel;

    typedef TemplateChannel<DoubleLinearSampler> DoubleLinearChannel;
    typedef TemplateChannel<FloatLinearSampler> FloatLinearChannel;
    typedef TemplateChannel<Vec2LinearSampler> Vec2LinearChannel;
    typedef TemplateChannel<Vec3LinearSampler> Vec3LinearChannel;
    typedef TemplateChannel<Vec4LinearSampler> Vec4LinearChannel;
    typedef TemplateChannel<QuatSphericalLinearSampler> QuatSphericalLinearChannel;

    typedef TemplateChannel<FloatCubicBezierSampler> FloatCubicBezierChannel;
    typedef TemplateChannel<DoubleCubicBezierSampler> DoubleCubicBezierChannel;
    typedef TemplateChannel<Vec2CubicBezierSampler> Vec2CubicBezierChannel;
    typedef TemplateChannel<Vec3CubicBezierSampler> Vec3CubicBezierChannel;
    typedef TemplateChannel<Vec4CubicBezierSampler> Vec4CubicBezierChannel;

}

#endif
